Superior semicircular canal dehiscence syndrome

Abstract

Superior semicircular canal dehiscence syndrome (SCDS) is caused by a bony defect of the superior semicircular canal. The bony defect allows low-frequency acoustic stimuli of high intensity to travel to the vestibular organ. This can be induced by sound stimuli or pressure stimuli leading to vertigo, torsional nystagmus, pulsatile tinnitus, hyperacusis, hearing loss and autophony. SCDS is diagnosed with provocative testing, audiometry, CT-scan, vestibular evoked myogenic potentials and electrocochleography. Treatment is conservative, however, surgery with occlusion of the defect can be necessary for debilitating symptoms, as argued in this review.